This invention relates generally to portable communications units, and more particularly, to an improved extendible antenna and microphone combination.
Portable communications units, such as mobile radios and wireless (or cellular) telephones, are continually being reduced in size and weight, as a result of semiconductor integrated circuitry and improvements in the power source and power utilization. It has become possible and highly desirable to provide personal hand-held portable communications units the size of a cigarette pack or even smaller.
One problem that arises with compact portable communication units is the lack of space available to separate the microphone, or mouthpiece, from the speaker, or earpiece. The ease and comfort of a conventional telephone, in which the handset includes spacing of the microphone and speaker to accommodate the distance between the user's mouth and ear is common, desirable, and acceptable. Users find it difficult to utilize communications units in which the microphone and speaker are not spaced apart four or more inches to enable usage without shifting the position of the communication unit between a talk position and a listen position. In addition, as communication units become smaller to enable and facilitate carrying in a shirt pocket, there is a corresponding but conflicting desire to shorten the required antenna and/or preclude the antenna from extending beyond the compact pocket-size communication unit, which may be on the order of only two by three inches.
An additional problem encountered in the miniaturization of portable communication units is the problem of background noise. The units are frequently utilized in an outdoors, noisy environment, and the small size of the instrument does not provide any significant barrier or sound baffle to the background noise. As a result, it is highly desirable to minimize or cancel background noise in such communication units.
Still further it is desirable to avoid electrical connections to any Extendible microphone, particularly in proximity to an antenna.